Are you a Firefox user? Do you want to make pesky ads disappear, manage your passwords better or view photos and videos in 3D? Bill Snyder of CIO.com highlights his favorite fun and free browser add ons that will work on both Firefox 5 and 4.

I was just getting used to the excellent version 4 of Mozilla's Firefox browser when those wild and crazy coders rolled out version 5 after just three months.

Version 4 was a huge leap forward from 3.6 and when it came out, I recommended it for its many new features, particularly the way it allows users to group tabs. Version 5 doesn't break a lot of new ground from the user's point of view, but it's solid and has some good stuff under the hood to make it more stable and developer friendly.

Like other versions of Firefox, many of the best goodies are contained in add ons, little programs that run within your browser. One problem with releasing versions so quickly is that it will take a while for developers of the add ons to make whatever changes are necessary for their apps to be compatible with the new browser.

Not all add ons that worked with 4 will work with 5, though many will and even more will work again in the future. For now, I've tested a number of my favorite add ons (plus some new ones) and picked five that will work on Firefox 5 as well as Firefox 4. All of these add ons are free.

If you install an add on and decide you don't want to keep it, uninstalling it is easy. Simply go to "tools" then "add ons" and then look for an icon labeled "extensions." When you click it, you'll see a list of your add ons and you can disable or remove them from there.

Even though I tend to use Firefox rather than Chrome these days, that doesn't mean I don't use Google services. In fact, I use quite a few. I really like this handy little add on. You can use it to display any of the dozens of Google services as buttons or as a space-saving dropdown menu next to your address bar. There are so many services to choose from in the settings menu box that you'll probably learn about some you'd never heard of.

I'm not the worst dressed guy in town, but Gucci? I don't think so. So I wasn't sorry to see the Gucci ad at the top of the New York Times page disappear after I installed
Adblock Plus.

This little add on doesn't do anything until you customize it. It can see everything a Web page attempts to load but it doesn't know whether this attempt should be blocked. That's when you need filters — filters will tell Adblock Plus what should be blocked. Usually, you won't create filters yourself. Instead you will add a filter subscription that is maintained by somebody else. If there's a page with ads you'd like to see, you can set Adblock Plus not to function on that page.

In addition to blocking ads, Adblock Plus actually speeds up your browsing since you won't have to wait for ads that load separately from the page.

LastPass is a handy password manager and form filler. Your passwords are kept in a "vault" online, which means they'll work across multiple browsers and computers. It makes it much easier to add security to your online life since you don't have to write your passwords down, or use the same one over and over again.

However, LastPass did suffer a data breach earlier this year. I was impressed with how well the company handled it, notifying users immediately and urging everyone to change their passwords. To my knowledge, no actual user data was lost. I have not stopped using it, but I keep an eye on all of my online accounts for unauthorized activity, which is something you should do whether you use as a password manager or not. My other favorite password manager, Roboform, doesn't yet work well with Firefox 5, though it is supported by Firefox 4.

This is an eye-candy app; not super useful but quite cool. Use it to get an innovative 3D view of photos or videos on the Web. It's the first 3D browser tool I've seen that doesn't have an impossibly complicated interface. It creates a wall of visual content you can sail by, stopping to play a video or zoom in on a photo. It's handy if you do a search on Google or Bing images and get lots of hits.

Cooliris works well on YouTube and a bunch of photo-sharing sites including Flickr, Picassa Web, and others, and integrates with Facebook and MySpace (if anyone still cares about MySpace). It won't work well on an older machine, but if your PC can handle Windows Vista or Windows 7, you'll be fine. There are also versions for the iPhone and iPad, but I haven't tried them yet.

Maybe I shouldn't include an add on that will help you waste time, but hey, who am I to judge? Asteroids Bookmarklet temporarily turns any Web site into an asteroids screen. Your cursor turns big, and just like you could in the original, vintage game, you move the enlarged cursor around with arrow keys and fire a laser cannon with the spacebar, and KaBoom — you blow up annoying parts of the page.

You don't even have to install it; simply drag the icon to your bookmarks bar, click on it, and you're ready to play — it's just a bit of JavaScript. When you need the page back, just refresh and it's back to work.

San Francisco journalist Bill Snyder writes frequently about business and technology. He welcomes your comments and suggestions. Reach him at bill.snyder@sbcglobal.net. Follow Bill Snyder on Twitter @BSnyderSF. Follow everything from CIO.com on Twitter @CIOonline

San Francisco journalist Bill Snyder writes frequently about business and technology. He writes the Tech's Bottom Line blog for InfoWorld, and his work appears regularly in CIO.com and the publications of Stanford's Graduate School of Business and the Haas School of Business at the University of California at Berkeley.